More severe US flu cases expected, deaths possible

A top US health official warned Monday that a virulent strain of swine flu that has caused more than 100 deaths in Mexico could lead to "more severe cases" and even deaths in the US.

"From what we understand in Mexico, I think people need to be ready for the idea that we could see more severe cases in this country and possibly deaths," Richard Besser, acting head of the US Centers for Disease Control and Prevention, told ABC television.

Besser said that while the outbreak of the disease hasn't caused death or serious illness in the United States, "I am not reassured that we have not seen more severe cases in this country."

"That's something that people have to be ready for. And we're looking for that," Besser said.